New PARKER HTG Product. Keep your Gravely zero-turn mower operating at its best with this complete transmission maintenance kit for Parker HTG transaxles. Genuine OEM parts ensure a precise fit, promoting optimal hydraulic performance, system reliability, and long-lasting durability in the toughest conditions. Kit includes (2) gallon bottles of premium HT-1000 hydrostatic transmission fluid, (2) oil filters, and (2) plugs with crush washers. Fits select Gravely PRO-STANCE ULTRA and PRO-TURN 500/600/MACH ONE models with Parker HTG transaxles. Make sure if this service kit is for your model by checking with the GRAVELY website.